1. Field of the Invention
The present invention relates to a heat and electric power supply system which generates and supplies heat and electric power at the same time and a method of operating the system.
2. Description of Prior Art
A lot of independent electric power plants, each operating a generator using an internal combustion engine or the like have been proposed as so-called co-generation facilities which generate hot water or steam and cold water by utilizing exhaust heat therefrom and supply thermal energy in the form of cold/heat. Some examples are disclosed in CLEAN ENERGY Vol. 6 No. 12 (1997, issued by JAPAN INDUSTRY) at pages 1 to 36. In many of these plants, a ratio between the maximum quantity electric power which can be supplied and a cold energy quantity or a heat energy quantity is fixed.
A cold/heat/electric power supply system which supplies electric power and thermal energy such as cold/heat at the same time can be realized by a combination of an absorption refrigerator which makes it possible to supply cold water/hot water at the same time by providing a change-over valve inside for example, and a generator which is driven by an internal combustion engine such as a diesel engine, gas engine, gas turbine or the like. Recently, a small-sized regenerative gas turbine provided with a regenerative heat exchanger has been developed and a cold/heat/electric power supply system using such a turbine also has been studied.
An example of a conventional cold/heat/electric power supply system is shown in FIG. 8, which employs a generator driven by a small-sized regenerative gas turbine and an absorption refrigerator. In this system, an exhaust gas 7 from the regenerative gas turbine 1 is led to the absorption refrigerator 2 which recovers heat from the exhaust gas in a regenerator and generates hot water 9 in a condenser and cold water 8 in an evaporator. In such a system as shown by this example, the maximum power generation output is limited by the maximum output of the regenerative gas turbine and it is impossible to increase the power generation output and to increase energy effectively utilized, even in the case where a demand such as air conditioning has decreased in middle season whereby a demand of cold/heat has decreased.
Further, some factors representative of the performance of the conventional system is shown in prior art items of FIG. 2 in the form of comparison of power generation efficiency and output between in the case where the above-mentioned system is operated in middle season (atmospheric temperature 15xc2x0 C. and humidity 30%) and in the case where the system is operated in summer (atmospheric temperature 38xc2x0 C. and humidity 60%). In summer, the air density decreases as the temperature increases and a mass flow rate of the air taken in a compressor of the regenerative gas turbine decreases, so that a recovery heat amount in a regenerative heat exchanger of the regenerative gas turbine and turbine output decrease and both the power generation terminal output and power generation efficiency change greatly, as shown in FIG. 2.
The present invention is made in view of the above-mentioned points, and an object of the present invention is to provide a heat and electric power supply system and an operation method thereof which enables the power generation output to increase.
In order to attain the above-mentioned object, a heat and electric power supply system according to the present invention comprises gas turbine equipment generating electric power, absorption refrigerating equipment recovering exhaust heat from the gas turbine equipment and generating thermal energy, and air cooling equipment fluidly connected to the gas turbine and the absorption refrigerating equipment and cooling air for power generation in the gas turbine equipment with the thermal energy generated in the absorption refrigerating equipment. An example of the air cooling equipment is a spray device for spraying cold water from the absorption refrigerator onto the air to be taken in a compressor of the regenerative gas turbine or a humidifier for humidifying the air from the compressor with hot water from the absorption refrigerator. The system can be provided with a heat recovering device for recovering heat from exhaust gas of the adsorption refrigerator and/or an accumulation type heat exchanger for recovering accumulating heat from exhaust gas of the adsorption refrigerator.
Further, in order to attain the above-mentioned object, according to the present invention, the operation method of a heat and electric power supply system which comprises gas turbine equipment and absorption refrigerating equipment recovering exhaust heat of the gas turbine equipment cooling or heating water, is characterized in that intake air of the gas turbine equipment is cooled by spraying or injecting the water generated in the absorption refrigerator onto the intake air. An example of the water used for cooling the intake water is at least one of cold water and hot water.